Smoking risks are strongly dose-related. Lung cancer risks are shown to leap from 10-fold to 70-fold with increased daily cigarette consumption. To reduce tobacco exposure and its corresponding hazards is a first step in transitioning resistant smokers who are unwilling or unable to commit to quitting. Traditionally, abstinence programs target the highly- motivated smoker ready to quit or take action. 80% of tobacco users, however, do not plan an attempt in the next six months. 50% will never quit. Reasons cited include unwillingness to forego the pleasure, discouragement with past failures, and intolerance of side effects. Occasionally, a "chink in the armor" appears and smokers become open to seriously cutting back. Smoking reduction is increasingly recognized as a first step in moving refractory tobacco users toward harm reduction and later stages of change, including the ideal of abstinence. Smoking reduction may reach deeper into pre-contemplative and intransigent segments who are otherwise unresponsive. Success at achieving more limited goals may rebuild self-efficacy loss. This study will demonstrate a technological breakthrough that delivers a scheduled reduction regimen programmed to decrease to and maintain usage at 50% of baseline. Sophisticated biomarkers will verity reduction in uptake of carcinogens, toxins and nicotine. PROPOSED COMMERCIAL APPLICATIONS: No broad-based protocol or commercial delivery instrument presently exists for the 80% of the 48-million smokers who are unwilling or unable to quit. This over-the-counter therapy device for scheduled reduction is used as: (1) a highly-effective self-help behavioral treatment for the most refractory smokers, (2) an adjunct to other medical care, and (3)a research tool to precisely monitor and tailor treatments.